PRMT1 Is Recruited via DNA-PK to Chromatin Where It Sustains the Senescence-Associated Secretory Phenotype in Response to Cisplatin

Summary: Protein arginine methyltransferase 1 (PRMT1) is overexpressed in various human cancers and linked to poor response to chemotherapy. Various PRMT1 inhibitors are currently under development; yet, we do not fully understand the mechanisms underpinning PRMT1 involvement in tumorigenesis and chemoresistance. Using mass spectrometry-based proteomics, we identified PRMT1 as regulator of arginine methylation in ovarian cancer cells treated with cisplatin. We showed that DNA-dependent protein kinase (DNA-PK) binds to and phosphorylates PRMT1 in response to cisplatin, inducing its chromatin recruitment and redirecting its enzymatic activity toward Arg3 of histone H4 (H4R3). On chromatin, the DNA-PK/PRMT1 axis induces senescence-associated secretory phenotype through H4R3me2a deposition at pro-inflammatory gene promoters. Finally, PRMT1 inhibition reduces the clonogenic growth of cancer cells exposed to low doses of cisplatin, sensitizing them to apoptosis. While unravelling the role of PRMT1 in response to genotoxic agents, our findings indicate the possibility of targeting PRMT1 to overcome chemoresistance in cancer. : Protein arginine methyltransferase 1 (PRMT1) overexpression is linked to cancer chemoresistance, but the mechanism is still unclear. Musiani et al. show that, upon cisplatin, PRMT1 is recruited by DNA-dependent protein kinase (DNA-PK) to chromatin, where it sustains the transcription of genes involved in the senescence-associated secretory phenotype (SASP), thus protecting cells from drug-induced apoptosis. Keywords: arginine methylation, MS-based proteomics, replication stress response, PRMT1, SASP, transcription, cisplatin, epigenetic drugs, DNA-P

HMG20B stabilizes association of LSD1 with GFI1 on chromatin to confer transcription repression and leukemia cell differentiation block

Pharmacologic inhibition of LSD1 induces molecular and morphologic differentiation of blast cells in acute myeloid leukemia (AML) patients harboring MLL gene translocations. In addition to its demethylase activity, LSD1 has a critical scaffolding function at genomic sites occupied by the SNAG domain transcription repressor GFI1. Importantly, inhibitors block both enzymatic and scaffolding activities, in the latter case by disrupting the protein:protein interaction of GFI1 with LSD1. To explore the wider consequences of LSD1 inhibition on the LSD1 protein complex we applied mass spectrometry technologies. We discovered that the interaction of the HMG-box protein HMG20B with LSD1 was also disrupted by LSD1 inhibition. Downstream investigations revealed that HMG20B is co-located on chromatin with GFI1 and LSD1 genome-wide; the strongest HMG20B binding co-locates with the strongest GFI1 and LSD1 binding. Functional assays demonstrated that HMG20B depletion induces leukemia cell differentiation and further revealed that HMG20B is required for the transcription repressor activity of GFI1 through stabilizing LSD1 on chromatin at GFI1 binding sites. Interaction of HMG20B with LSD1 is through its coiled-coil domain. Thus, HMG20B is a critical component of the GFI1:LSD1 transcription repressor complex which contributes to leukemia cell differentiation block

Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities

Background: Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. the possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here.Methodology/Principal Findings: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a) a protein epitope of Candida albicans cell wall stress mannoprotein; b) a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c) a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. the inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains.Conclusions/Significance: the high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. the easy production and low cost of small sized synthetic peptides representing Ig CDRs and the possibility of peptide engineering and chemical optimization associated to new delivery mechanisms are expected to give rise to a new generation of therapeutic agents.Department of Education, Universities and Research, Basque GovermentFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Istituto Superiore di Sanita, National Research Project on A.I.D.S.Cariparma Banking FoundationBrazilian National Research CouncilUniv Parma, Sez Microbiol, Dipartimento Patol, I-43100 Parma, ItalyUniv Basque Country, Fac Med Odontol, Dept Inmunol, Microbiol Parasitol, Bilbao, SpainUniv Basque Country, Dept Enfermeria I, Bilbao, SpainUniv Milan, Dipartimento Sci Cliniche L Sacco, Sez Malattie Infettive Immunopatol, Milan, ItalyUniv Studi Parma, Dipartimento Clin Med, Nefrol Sci Prev, Parma, ItalyUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilDepartment of Education, Universities and Research, Basque Goverment: IT-264-07FAPESP: 06/50634-2Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 50G.30Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 40D.14Cariparma Banking Foundation: 2004.0190Brazilian National Research Council: research fellowshipWeb of Scienc

An Approach to an Insular self-contained waste management system with the aim of maximizing recovery while limiting transportation costs

This study is focused on definition of the typology, capacity and location of waste treatment and disposal facilities for use in both present and future management scenarios on the larger Mediterranean islands, using Sicily as a case study. Following estimation of the amount of waste produced in Sicily and the proposal of a pathway aimed at rapidly achieving the 50% recovery target established by the European Union, a series of progressive and alternative scenarios for the management of residual waste have been proposed and analyzed by means of the software platform TransCad in terms of “facility location” and “minimum-cost flow” problems. The cost of transportation was calculated as the sum of different cost components related to distance traveled, staff involved, and vehicle used to collect waste, including fuel costs, tire costs, road tax and truck maintenance costs. The different scenarios were critically compared in terms of transportation costsAnalysis of traffic flows allowed us to ascertain the general framework of increased traffic elicited by the proposed scenarios and assess the impact caused by an increase in “trucks per day” along three critical sections of the road network in Sicily. Overall transportation costs corresponded to approximately 10% of treatment/disposal costs for all scenarios, highlighting therefore how transportation costs should not be over-inflated or used to condition public acceptance as to the location, size and typology of the facilitie

Thiol–yne chemistry for 3D printing: exploiting an off-stoichiometric route for selective functionalization of 3D objects

An alkyne monomer bis(propargyl) fumarate is synthesized and used to produce DLP-3D printable formulations with a thiol exploiting photoinduced thiol-yne reaction. By preparing mixtures containing different relative ratios of two monomers, it is possible to obtain polymers exposing different unreacted functional groups on their surface. The reactivity of the formulations toward visible light irradiation is studied by ATR analysis and photorheology tests, the printability with DLP equipment is demonstrated and the thermomechanical properties of the obtained polymers are investigated by DMA. Changing the printing formulation during the printing process, objects exposing either triple bonds or thiol groups or a mix of them can be obtained, and the presence of unreacted groups is confirmed by XPS analysis; this property can be exploited to selectively functionalize the built parts in a dedicated post process. As a proof of concept, a simple hybrid structure is treated with an azide-terminated squaraine dye, to exploit a 'click' reaction with the alkyne groups available. The fluorescence of the functionalized structure is observed with a spinning disk confocal microscope. Such a strategy can allow producing 3D objects with a controllable structure just by varying the relative ratio of the co-monomers in the formulations during the printing process

3D Printing with the Commercial UV-Curable Standard Blend Resin: Optimized Process Parameters towards the Fabrication of Tiny Functional Parts

Stereolithography 3D printing is today recognized as an effective rapid prototyping technique in the field of polymeric materials, which represents both the strengths and the weaknesses of this technique. The strengths relate to their easy handling and the low energy required for processing, which allow for the production of structures down to the sub-micrometric scale. The weaknesses are a result of the relatively poor mechanical properties. Unfortunately, the choice of the right material is not sufficient, as the printing parameters also play a crucial role. For this reason, it is important to deepen and clarify the effect of different printing conditions on final product characteristics. In this paper, the behavior of commercial Standard Blend (ST Blend) acrylic resin printed with stereolithography (SL) apparatus is reported, investigating the influence of printing parameters on both the tensile properties of the printed parts and the build accuracy. Twenty-four samples were printed under different printing conditions, then dimensional analyses and tensile tests were performed. It was possible to find out the optimum printing setup to obtain the best result in terms of mechanical resistance and printing accuracy for this kind of resin. Finally, a micrometric spring was printed under the optimal conditions to demonstrate the possibility of printing accurate and tiny parts with the commercial and inexpensive STBlend resin

Pharmacological inhibition of LSD1 triggers myeloid differentiation by targeting GSE1 oncogenic functions in AML

The histone demethylase LSD1 is over-expressed in hematological tumors and has emerged as a promising target for anticancer treatment, so that several LSD1 inhibitors are under development and testing, in preclinical and clinical settings. However, the complete understanding of their complex mechanism of action is still unreached. Here, we unraveled a novel mode of action of the LSD1 inhibitors MC2580 and DDP-38003, showing that they can induce differentiation of AML cells through the downregulation of the chromatin protein GSE1. Analysis of the phenotypic effects of GSE1 depletion in NB4 cells showed a strong decrease of cell viability in vitro and of tumor growth in vivo. Mechanistically, we found that a set of genes associated with immune response and cytokine-signaling pathways are upregulated by LSD1 inhibitors through GSE1-protein reduction and that LSD1 and GSE1 colocalize at promoters of a subset of these genes at the basal state, enforcing their transcriptional silencing. Moreover, we show that LSD1 inhibitors lead to the reduced binding of GSE1 to these promoters, activating transcriptional programs that trigger myeloid differentiation. Our study offers new insights into GSE1 as a novel therapeutic target for AML.</p

Role of Strain Rate in the Pathogenesis of Ventilator-Induced Lung Edema

Objective: Lungs behave as viscoelastic polymers. Harms of mechanical ventilation could then depend on not only amplitude (strain) but also velocity (strain rate) of lung deformation. Herein, we tested this hypothesis. Design: Laboratory investigation. Setting: Animal unit. Subjects: Thirty healthy piglets. Interventions: Two groups of animals were ventilated for 54 hours with matched lung strains (ratio between tidal volume and functional residual capacity) but different lung strain rates (ratio between strain and inspiratory time). Individual strains ranged between 0.6 and 3.5 in both groups. Piglets ventilated with low strain rates had an inspiratory-to-expiratory time ratio of 1:2-1:3. Those ventilated with high strain rates had much lower inspiratory-to-expiratory time ratios (down to 1:9). Respiratory rate was always 15 breaths/min. Lung viscoelastic behavior, with ventilator setting required per protocol, was "quantified" as dynamic respiratory system hysteresis (pressure-volume loop [in Joules]) and stress relaxation (airway pressure drop during an end-inspiratory pause [in cm H2O]). Primary outcome was the occurrence of pulmonary edema within 54 hours. Measurements and Main Results: On average, the two study groups were ventilated with well-matched strains (2.1 ± 0.9 vs 2.1 ± 0.9; p = 0.864) but different strain rates (1.8 ± 0.8 vs 4.6 ± 1.5 s-1; p < 0.001), dynamic respiratory system hysteresis (0.6 ± 0.3 vs 1.4 ± 0.8 J; p = 0.001), and stress relaxation (3.1 ± 0.9 vs 5.0 ± 2.3 cm H2O; p = 0.008). The prevalence of pulmonary edema was 20% among piglets ventilated with low strain rates and 73% among those ventilated with high strain rates (p = 0.010). Conclusions: High strain rate is a risk factor for ventilator-induced pulmonary edema, possibly because it amplifies lung viscoelastic behavior

Contrast-enhanced mammography BI-RADS: a case-based approach to radiology reporting

Abstract Contrast-enhanced mammography (CEM) is a relatively recent diagnostic technique increasingly being utilized in clinical practice. Until recently, there was a lack of standardized reporting for CEM findings. However, this has changed with the publication of a supplement in the Breast Imaging Reporting and Data System (BI-RADS). A comprehensive understanding of CEM is essential for further enhancing its role in both screening and managing patients with breast malignancies. CEM can also be beneficial for problem-solving, improving the management of uncertain breast findings. Practitioners in this field should become more cognizant of how and when to employ this technique and interpret the various CEM findings. This paper aims to outline the key findings in the updated version of the BI-RADS specifically dedicated to CEM. Additionally, it will present some clinical cases commonly encountered in clinical practice. Critical relevance statement Standardized reporting and a thorough understanding of CEM findings are pivotal for advancing the role of CEM in screening and managing breast cancer patients. This standardization contributes significantly to integrating CEM as an essential component of daily clinical practice. Key points • A complete knowledge and understanding of the findings outlined in the new BI-RADS CEM are necessary for accurate reporting. • BI-RADS CEM supplement is intuitive and practical to use. • Standardization of the CEM findings enables more accurate patient management. Graphical Abstrac